屈服强度500MPa级耐候焊丝焊缝的强韧化机制  

Mechanism of Strengthening and Toughening of Welding Seam Made by Weatherproof Welding Wire with Yield Strength of 500 MPa Grade

作　　者：任学堂 肖丙政 胡兵 成建兵 黄俊文 REN Xuetang;XIAO Bingzheng;HU Bing;CHENG Jianbing;HUANG Junwen(Nanjing Iron&Steel Co.,Ltd.,Nanjing Jiangsu 066000,China;School of Materials Science and Engineering,Yanshan University,Qinhuangdao Hebei 066000,China)

机构地区：[1]南京钢铁股份有限公司,江苏南京210000 [2]燕山大学材料科学与工程学院,河北秦皇岛066000

出　　处：《上海金属》2024年第2期34-39,共6页Shanghai Metals

摘　　要：采用ER65NH-A焊丝对Q500qENH钢进行了CO_(2)保护焊。分析了焊丝的Ni含量与焊缝的显微组织和力学性能之间的关系。结果表明:当焊丝的Ni质量分数从0.78%增加至1.65%时,焊缝抗拉强度从706 MPa提高到了732 MPa,屈服强度从579 MPa提高到了614 MPa,-40℃冲击吸收能量(KV2)从46 J提高到了84 J。焊缝力学性能改善的机制为:Ni含量的增加提高了奥氏体的稳定性,细化了焊缝柱状晶区和焊道热影响区组织,焊缝发生脆性断裂的倾向减小。CO_(2)-shieled arc welding was performed on Q500qENH steel by using ER65NH-A wire.The relationship among nickel content in the wire,microstructure and mechanical properties of the weld was analyzed.The results showed that as the mass fraction of nickel in the wire increased from 0.78%to 1.65%,the weld increased in tensile strength from 706 to 732 MPa,in yield strength from 579 to 614 MPa,and in-40℃impact absorbed energy(KV2)from 46 to 84 J.The mechanism of an improvement in the mechanical properties of the weld was that the increase in nickel content enhanced stability of austenite,refined microstructures of columnar crystal zone and heat-affected zone of the weld run,and reduced the tendency of the weld to produce brittle fracture.

关 键 词：耐候焊丝 Ni含量 焊缝 低温韧性 抗拉强度 

分 类 号：TG446[金属学及工艺—焊接]